They clog up. Very quickly, and very often you will find yourself lifting these trickling sacs of water out of your treatment system for replacement. Maybe the bag will be able to handle one or two washes and reuses before it needs to be discarded and switched out with a new bag. But especially if you have many bags, you’re in for a very pricey and timely commitment. Accidentally drop a dirty bag during a switch (they can get pretty heavy) and you’ve contaminated all your clean water. Bag filters are useful and effective in many applications, but if you are dealing with the high solids loading associated with coagulation or flocculation, you might like to try a different method.
Filtration is a necessary component of essentially any water treatment system. Whether you are using bar-racks or nanomembranes, the issue of clogging is bound to arise. The frequency of clogging is a simple matter of the area of your filter versus the amount of matter being stripped out of your water. The issue with the bag filter is that it can only offer so much surface area and cannot be effectively cleaned for repeated reuse. In coagulation and flocculation operations a large volume of waste particles are produced that must be removed from the water. The combination of these factors leads to very frequent clogging and lots of headaches for maintenance in this particular application.
Whatever shall we do?
The solution to the frustrations of filter bags is the automatic indexing gravity bed filter. This long title describes the ingenuously simple technology that takes care of clogging and filter replacement for you. As water is gravity-fed onto a sheet of filter paper, draped across a conveyor belt, solids are deposited and water passes through to be collected in a tray. These solids accumulate until water can no longer flow through and begins to puddle up on the bed. This puddling causes a sensor float to rise which initiates the advancement of the clogged paper into a collection bin as it is replaced with fresh paper from a large roll. As a result the process continues uninterrupted while you are off worrying about other things. All used paper and deposited solids can be taken out with the trash while a single roll may replenish lost paper for up to a year. In the end you can save a lot of money and time by simply using a smarter filter.
If you are looking to install a water treatment system or if you are simply fed-up with filter bags don’t hesitate to contact the experts at HPI Processes, Inc. for top-notch consultations and service.